refactor: 清理 reviewSimpleData.ts 未使用的程式碼

移除未使用的 ApiResponse interface、MOCK_API_RESPONSE 常數和 sortCardsByPriority 舊版函數，簡化程式碼結構。

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/lib/data/reviewSimpleData.ts

@@ -43,18 +43,6 @@ export interface QuizItem {
   cardData: CardState         // 詞卡數據引用
 }
 
-export interface ApiResponse {
-  success: boolean
-  data: {
-    flashcards: ApiFlashcard[]
-    count: number
-  }
-  message: string | null
-  timestamp: string
-}
-
-// 模擬API響應數據 (直接使用真實API格式)
-export const MOCK_API_RESPONSE: ApiResponse = apiSeeds as ApiResponse
 
 // 為詞卡添加延遲計數狀態
 const addStateFields = (flashcard: ApiFlashcard, index: number): CardState => ({
@@ -66,7 +54,7 @@ const addStateFields = (flashcard: ApiFlashcard, index: number): CardState => ({
 })
 
 // 提取詞卡數據 (方便組件使用)
-export const SIMPLE_CARDS = MOCK_API_RESPONSE.data.flashcards.map(addStateFields)
+export const SIMPLE_CARDS = (apiSeeds as any).data.flashcards.map(addStateFields)
 
 // 生成線性測驗項目序列
 export const generateQuizItems = (cards: CardState[]): QuizItem[] => {
@@ -123,25 +111,6 @@ export const sortQuizItemsByPriority = (quizItems: QuizItem[]): QuizItem[] => {
   })
 }
 
-// 舊版排序函數 (保留向後兼容)
-export const sortCardsByPriority = (cards: CardState[]): CardState[] => {
-  return cards.sort((a, b) => {
-    // 1. 已完成的卡片排到最後
-    if (a.isCompleted && !b.isCompleted) return 1
-    if (!a.isCompleted && b.isCompleted) return -1
-
-    // 2. 未完成卡片按延遲分數排序 (越少越前面)
-    const aDelayScore = a.skipCount + a.wrongCount
-    const bDelayScore = b.skipCount + b.wrongCount
-
-    if (aDelayScore !== bDelayScore) {
-      return aDelayScore - bDelayScore
-    }
-
-    // 3. 延遲分數相同時按原始順序
-    return a.originalOrder - b.originalOrder
-  })
-}
 
 // 生成詞彙選擇測驗選項
 export const generateVocabOptions = (correctWord: string, allCards: CardState[]): string[] => {